The overall object of the studies is to measure the tolerance of normal tissues to cancer treatment modalities. Specifically, we wish to study the interaction of hyperthermia and radiation in producing injury to the spermatogenic epithelium, to quantify the dose-response relationship of jejunal mucosa, testes and hair in the clinically-relevant dose range, and to evaluate the kinetics of the late response of irradiated skin and how this may be modified by prior radiotherapy or subsequent innoculation of fibroblasts into the dermis.